1.Application of element-tagged immunoassay combined with inductively coupled plasma mass spectrometry in HCG detection
Danna PU ; Wencan JIANG ; Xinyu WEN ; Guanghong GUO ; Ping LI ; Chengbin WANG
Chinese Journal of Laboratory Medicine 2020;43(3):284-290
Objective:To establish an inductively coupled plasma mass spectrometry (ICP-MS) based immunoassay method for the quantitative detection of human chorionic gonadotropin (HCG), and evaluate the clinical applicability of this method.Methods:Sm was selected as element tags, and the HCG quantitative detection system was established by double antibody sandwich method. The dosage of biotinylated antibody and reaction time were optimized. According to EP documents of Clinical and Laboratory Standards Institute (CLSI) and related standards, the analytical performance was evaluated after the establishment of the assay, including the limit of blank (LOB), linearity, precision, recovery, cross reactivity and interference test. And 88 clinical samples were measured using the new method compared to the electrochemical immunoassay (ECLIA) method.Results:Total process completed within 30 min after optimization, and the optimal biotinylated antibody dosage was 0.5 μl. The LOB was 0.29 mIU/ml. The linearity was good within the range of 1.16-8 365.62 mIU/ml with the linear correlation coefficient greater than 0.995 ( R2=0.998 0), the recovery was 97.53%-102.01%. Both intra-and inter-assay coefficients of variation of the high-value sample and the low-value sample were less than 10%. And there was no significant cross-reaction with Luteinizing hormone (LH), follicular stimulating hormone (FSH), and thyroid-stimulating hormone (TSH). The interference bias caused by different concentrations of interference substances was less than 10%. When compared with the ECLIA method for clinical sample detection, the proposed method showed a significant correlation( R2=0.960 0). Conclusion:The proposed ICP-MS base immunoassay for HCG detection has good accuracy, high sensitivity and specificity, and the results of analytical performance verification meet the clinical requirements, which provides experimental basis for the clinical application of this method.
2.Detection rate and influencing factors of suspected scoliosis among primary and middle school students in Dali Bai Autonomous Prefecture
Guanghong PU ; Xiaowen WANG ; Zhi ZHAO ; Jiang LU ; Caihong LI ; Zixiang YAN ; Yiwen WANG ; Li ZHANG ; Yingsong WANG
Chinese Journal of Orthopaedics 2022;42(21):1433-1440
Objective:To investigate the epidemiological characteristics and influencing factors of scoliosis among primary and middle school students in Dali Bai autonomous prefecture.Methods:A total of 176,729 students aged 6-18 years from 380 primary and secondary schools in eight counties of Dali Bai Autonomous Prefecture were screened for spinal health by visual method, Adams forward bend test and scoliometer measuring the angle of trunk rotation from September to November 2021. The angle of trunk rotation ≥5° or visual method retest positive was used as a positive standard to confirm suspected scoliosis population. Demographic data of the screening population including name, gender, age and ethnicity were collected. The average altitude of the community or village committee in the screening area was recorded. Binary logistic regression analysis was used to screen the influencing factors of scoliosis.Results:There were 176,729 people planned to complete the screening. A total of 140,026 people were actually completed screening with completion rate 79.23%. A total of 3,190 (2.28%) suspected scoliosis positive people were detected. The detection rate of female was 2.52%, which was higher than that of male 2.03% (χ 2=37.18, P<0.001). The detection rate of 10-18 years old group was 2.90%, which was higher than that of 6-9 years old group 0.70% (χ 2=620.79, P<0.001). There was a significant difference in the detection rate among different age groups from 6 to 18 years old (χ 2=1,451.00, P<0.001). The detection rate of Han population was 2.67%, which was higher than that of non-Han population 2.15% (χ 2=31.06, P<0.001). In non-Han population, the detection rate of Bai population was 2.07%, which was lower than that of non-Bai population 2.26% (χ 2=4.02, P=0.045). Trend chi-square test showed significant difference in the detection rate of scoliosis among the general population, 10-18 years old population and 6-9 years old population in the altitude <1,500 m, 1,500-1,599 m, 1,600-1,699 m, 1,700-1,799 m, 1,800-1,899 m, 1,900-1,999 m, 2,000-2,099 m, 2,100-2,199 m, 2,200-2,299 m and ≥2,300 m groups (χ 2=249.02, 195.64, 24.46, P<0.05). Binary logistic regression analysis showed that the risk of scoliosis was lower in males than that in females ( OR=0.82, P<0.001). The risk of scoliosis was increased in 10-18 years old compared with that in 6-9 years old ( OR=0.12, P<0.001). The risk of scoliosis was low in Bai population compared with that in Han populations ( OR=0.75, P<0.001). The altitude ≥2,000 m was a risk factor ( OR=1.52, P<0.001). Conclusion:The detection rate of suspected scoliosis in primary and middle school students in Dali Bai Autonomous Prefecture was 2.28%. Female, aged 10-18 years, Han populations, and residence in altitude ≥2,000 m might be the risk factors for scoliosis.